公开(公告)号：US20200033284A1

公开(公告)日：2020-01-30

申请号：US16337498

申请日：2017-09-06

Applicant: ams International AG

Inventor： Rohit RANGANATHAN ,  Sanjeev Praphulla Chandra NYSHADHAM ,  Krishna Kanth AVALUR ,  Ravi Kumar ADUSUMALLI ,  Prasad PONNADA

IPC: G01N27/12

Abstract: A measurement circuitry (MC) for evaluating a resistance of a resistive gas sensor (GS) comprises a first current path (P1), wherein a first logarithmic compression circuit (LC1) is arranged in the first current path (P1). A reference resistor (Rreference) and a second logarithmic compression circuit (LC2) is arranged in a second current path (P2) of the measurement circuitry (MC). A voltage generator (VG) provides a fixed voltage excitation for the resistive gas sensor (GS) and the reference resistor (Rreference). A first current (I1) received from the resistive gas sensor (GS) flows from the gas sensor (GS) via the first current path (P1) into the first logarithmic compression circuit (LC1). An evaluation circuit (EC) determines the resistance (Rs) of the resistive gas sensor (GS) in dependence on a first and second output signal (Ve1, Ve2) of the first and the second logarithmic compression circuit (LC1, LC2).

公开(公告)号：US20240183980A1

公开(公告)日：2024-06-06

申请号：US18285181

申请日：2022-03-29

Applicant: ams International AG

Inventor： Krishna Kanth AVALUR ,  Rajesh GUPTA

IPC: G01S17/04 ,  G01S7/481 ,  G09G3/3208

CPC classification number: G01S17/04 ,  G01S7/4816 ,  G09G3/3208 ,  G09G2320/0626 ,  G09G2360/14

Abstract: An optical proximity sensor comprises a photodiode, a light source configured to emit light and a measurement circuit coupled to the photodiode. The measurement circuit is configured to measure light received by the photodiode in a first phase when the light source is turned off and in a second phase when the light source is turned on. The measurement circuit determines the difference between the light measured in the first and second phases, wherein the first phase for off measurement is longer than the second phase for on measurement.